Process for breaking petroleum emulsions



Patented Jan. 27, 1953 PROCESS FOR BREAKING PETROLEUM EMULSIONS Melvin De Grocte, University City, Mo., assignor to Petrolite Corporation, a corporation of Delaware No Drawing. Application December 1, 1950, Serial No. 198,751

11 Claims.

This invention relates to petroleum emulsions of the water-in-oil type that are commonly referred to as cut oil, roily oil, emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion.

One object of my invention is to provide a novel process for breaking or resolving emulsions of the kind referred to.

Another object of my invention is to provide an economical and rapid process for separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude oil and relatively soft waters or weak brines. Controlled emulsification and subsequent demulsification under the conditions just mentioned, are of significant value in removing impurities particularly inorganic salts from pipeline oil.

Demulsiflcation as contemplated in the present application includes the preventive step of commingling the demulsifier with the aqueous component which would or might subsequently become either phase of the emulsion, in absence of such precautionary measure. Similarly, such demulsifier may be mixed with the hydrocarbon component.

The demulsifying agent employed in the pres ent process is a fractional ester obtained from a polycarboxy acid and a diol containing both nitrogen and sulfur obtained by the oxypropylation of a sulfonamide having not more than 7 uninterrupted carbon atoms in any single radical and containing a phenyl radical. For all practical purposes this limits the sulionamide to benzene sulfonamide, toluene sulfonamide, and sulfonic amides obtained from anisole, phenetole, or sulfonamides obtained from comparable ethers in which the alkyl group contains more than 3 carbon atoms but not over 7 carbon atoms, and containing the phenyl radical. Furthermore, the dihydroxylated compound prior to esterification must. be water-insoluble and kerosene-soluble. Momentarily ignoring certain variants of structure which will be considered subsequently the demulsifier may be exemplified by the following formula:

II H00cp Rt; oHflo3)..N- o3Hfio),.'oR oo0H),.

in which R is a member of the class of aromatic hydrocarbon radicals and oxygen-interrupted aromatic hydrocarbon radical having a single ether linkage, with the proviso that the entire class be free from any radical having more than 7 uninterrupted carbon atoms in a single group; and n and n are whole numbers with the proviso that n plus 21. equals a sum varying from 15 to n" is a whole number not over 2 and R is the radical of the polycarboxy acid COOH preferably free from any radicals having more than 8 uninterrupted carbon atoms in a single group, and with the further proviso that the parent dihydroxy compound prior to esterification be water-insoluble and kerosene-soluble.

Attention is directed to the co-pending application of C. M. Blair, Jr., Serial No. 70,811, filed January 13, 1949 (now Patent 2,562,878, granted August '7, 1951), in which there is described, among other things, a process for breakin petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of an esterification product of a dicarboxylic acid and a polyalkylene glycol in which the ratio of equivalents of polybasic acid to equivalents of polyalkylene glycol is in the range of 0.5 to 2.0, in which the alkylene group has from 2 to 3 carbon atoms, and in which .the molecular weight of the product is between 1,500 and 4,000.

Similarly, there have been used esters of dicarboxy acids and polypropylene glycols in which 2 moles of the dicarboxy acid ester have been reacted with one mole of a polypropylene glycol having a molecular weight, for example, of 2,000 so as to form an acidic fractional ester. Subsequent examination of what is said herein in comparison with the previous example as well as the hereto appended claims will show the line of delineation between such somewhat comparable compounds. Of greater significance, however, is what is said subsequently in regard to the structure of the parent diol as compared to polypropylene glycols whose molecular weights may vary from 1,000 to 2,000.

As previously stated one preferably uses benzene sulfonamide or toluene sulfonamide. I have used either one or both of these amides and also after treatment with 1, 2, 3 or 4 moles of ethylene oxide. If there is any choice I prefer to use benzene sulfonamide or oxyethylated benzene sulfonamide particularly an oxyethylated benzene sulfonamide which has been treated with either one mole or two moles of ethylene oxide.

Obviously a suitable sulfonamide such as benzene sulfonamide or toluene sulfonamide could be treated with compounds which would yield a derivative having both a hydroxyl radical and a side chain ether radical as, for example reactions involving benzene sulfonamide on the one hand and allyl glycidyl ether, glycidyl isopropyl ether, glycidyl phenyl ether, or the like, on the other hand. such compounds, of course, could still be treated with a mole or more of ethylene oxide before reacting with propylene oxide to produce the oxypropylated derivatives described subsequently in greater detail.

It is to be noted that another type of sulfonamide having 2 terminal hydroxyl radicals can be employed to make compounds comparable to those described herein, both at the end of the oxypropylation stage and at the end of the esterification stage. These particular compounds are also effective for demulsification and for the various other purposes herein described. Such compounds are obtained from a substituted amine free from a hydroxylated radical. In other words, instead of being sulfonamides derived from ammonia, ethanolamine, or diethanolamine, they are amides derived from propylamine, butylamine, amylamine, hexylamine, benzylamine, aniline and the like. The sulfonamides thus obtained are comparable to those previously described with this exception; a hydrocarbon radical having less than 8 carbon atoms replaces one of the amido hydrogen atoms and thus there is only one amido hydrogen atom available for reaction with propylene oxide if such reaction were conducted without an intermediate step. However, such compound can be converted into a dihydroxylated compound by reaction with glycide or, if desired, by first reacting with ethylene oxide and then with glycide. This is illustrated in the following two formulas showing such derivatives obtained from n-amyl benzene sulfonamide:

Amyl

CaHs

Amyl

/O H C 1H4 O C 3115 What has been said previously in regard to the materials herein described and particularly for use as demulsifiers with reference to fractional esters, may be and probably is an oversimplification for reasons which are obvious on further examination. The assumption has been and it is believed to be largely true that the oxypropylation of a sulfonamide produces a dihydroxylated compound. There is some evidence based on abnormal molecular weights that at least in part under certain conditions one does not necessarily obtain a hundred per cent dihydroxylated compound but one may obtain a monohydroxylated compound due to the fact only one amido hydrogen is attacked by the alkylene oxide and this would be true whether it happened to be propylene oxide or some other oxide, such as ethylene oxide.

For instance, in my co-pending application, Serial No. 198,755, filed December 1, 1950, there i involved a similar amide, i. e., the amide of a monocarboxy acid as differentiated from an amide of a sulfonic acid. An example of such amide is acetamide. In said co-pending application in regard to the oxypropylation of the cycloacetamide the following two paragraphs appear:

As far as acetamides themselves are concerned it is well known that tautomerism takes place as shown by the following:

Owing to the presence of active hydrogens in amides, these compounds react with metals to form salts. For example, acetamide reacts with metallic sodium to yield a sodium salt. The greatest difficulty results in attempting to arrive at a possible structure of this salt; it may be either one of the following:

ONa CHa-QE-bP-Na CH3 =N-H Since oxypropylations are conducted in presence of caustic soda or an equivalent catalyst, such as sodium methylate, in the substantial absence of water there is a question as to whether or not some sort of structural change may be involved or perhaps some other type of reaction involving an alpha hydrogen atom attached to the carbon atom which, in turn, is joined to the carbonyl carbon atom. All this is merely a matter of speculation but it does explain why it is necessary to include claims directed to description of the ultimate product in terms of the method of manufacture, and also in terms of structure, although the latter must be interpreted in light of what has been said above and which will be amplified subsequently.

The situation in regard to the isoamide in the case of a sulfonamide has been subjected to less exploration and perhaps is a matter of even greater speculation. In the instant situation also oxypropylation takes place in the presence of an alkaline catalyst. Hantzsch (Ber. 1901, 34, 3148) suggested that the salts might be derived from the isoamide structure, R.SO(OH) :NH, which is analogous to the isoamide structure for the carboxylic amides discussed above.

If this is the case it is purely a matter of speculation at the moment because apparently there is no data which determines the matter completely under all conditions of manufacture and one has a situation somewhat comparable to the acylation of monoethanolamine or diethanolamine, i. e., acylation can take place involving either the hydrogen atom attached to oxygen or the hydrogen atom attached to nitrogen.

However, as far as the herein described compounds are concerned it would be absolutely immaterial except that one would have in part a compound which might be a fractional ester and might also have an amide structure with only one carboxyl radical of the polycarboxylated reactant involved. It would be comparable to obtaining a dibasic compound by reacting one mole of ethylenethanolamine with two moles of phthalic anhydride to produce an acidic ester amide.

By and large it is believed the materials obtained are fractional esters obtained from dihydroxylated compounds as hereinafter stated in greater detail.

However, in order to present the invention in its broadest aspect it is necessary to include a claim directed to the method of manufacture insofar that claims based on compositions are susceptible to the limitation previously pointed out unless interpreted as including the obvious equivalent.

For convenience, what is said hereinafter will be divided into five parts;

Part 1 is concerned with the preparation of the oxypropylation derivatives of the specified sulfonamides;

Part 2 is concerned with the preparation of the esters from the oxypropylated derivatives;

Part 3 is concerned with the structure of the oxypropylation products obtained from the specified sulfonamides;

Part 4 is concerned with the use of the products herein described as demulsifiers for breaking water-in-oil emulsions; and

Part 5 is concerned with certain derivatives which can be obtained from the oxypropylated sulfonamides. In some instances such derivatives are obtained by modest oxyethylation preceding the oxypropylation step, or oxypropylation followed by oxyethylation. This results in diols having somewhat different properties which can then be reacted with the same polycarboxy acids or anhydrides described in Part 2 to give effective demulsifying agents. For this reason a description of the apparatus makes casual mention of oxyethylation. For the same reason there is brief mention of the use of glycide.

PART 1 For a number of well known reasons equipment, whether laboratory size, semi-pilot plant becomes obvious that it is adapted for oxyethylation as well as oxypropylation.

oxypropylations are conducted under a wide variety of conditions, not only in regard to presence or absence of catalyst, and the kind of catalyst, but also in regard to the time of reaction, temperature of reaction, speed of reaction, pressure during reaction, etc. For instance, oxyalkylations can be conducted at temperatures up to approximately 200 C. with pressures in about the same range up to about 200 pounds per square inch. They can be conducted also at temperatures approximating the boiling point of water or slightly above, as for example 95 to 120 C. Under such circumstances the pressure will be less than 30 pounds per square inch unless some special procedure is employed as is sometimes the case, to wit, keeping an atmosphere of inert gas such as nitrogen in the vessel during the reaction. Such low temperature-low reaction rate oxypropylations have been described very completely in U. S. Patent No. 2,448,664, to H. R. Fife,

6 action speed oxypropylations require considerable time, for instance, 1 to 7 days of 24 hours each to complete the reaction they are conducted as a rule whether on a laboratory scale, pilot plant scale, or large scale, so as to operate automatically. The prior figure of seven days applies especially to large-scale operations. I have used conventional equipment with two added automatic features; (a) a solenoid controlled valve which shuts off the propylene oxide in event that the temperature gets outside a predetermined and set range, for instance, to C., and (b) another solenoid valve which shuts off the propylene oxide (or for that matter ethylene oxide if it is being used) if the pressure gets beyond a predetermined range, such as 25 to 35 pounds. Otherwise, the equipment is substantially the same as is commonly employed for this purpose where the pressure of reaction is higher, speed of reaction is higher, and time of reaction is much shorter. In such instances such automatic controls are not necessarily used.

Thus, in preparing the various examples I have found it particularly advantageous to use laboratory equipment or pilot plant which is designed to permit continuous oxyalkylation whether it be oxypropylation or oxyethylation. With certain obvious changes the equipment can be used also to permit oxylalkylation involving the use of glycide where no pressure is involved except the vapor pressure of a solvent, if any, which may have been used as a diluent.

As previously pointed out the method of using propylene oxide is the same as ethylene oxide. This point is emphasized only for the reason that the apparatus is so designed and constructed as to use either oxide.

The oxypropylation procedure employed in the preparation of the oxyalkylated derivatives has been uniformly the same, particularly in light of the fact that a continuous automatically-controlled procedure was employed. In this procedure the autoclave was a conventional autoclave made of stainless steel and having a capacity of pproximately 15 gallons and a working pressure of one thousand pounds gauge pressure. This pressure obviously is far beyond any requirement as far as propylene oxide goes unless there is a reaction of explosive violence involved due to accident. The autoclave was equipped with the conventional devices and openings, such as the variable-speed stirrer operating at speeds from 50 R. P. M. to 500 R. P. M.; thermometer well and thermocouple for mechanical thermometer; emptying outlet; pressure gauge, manual vent line; charge hole for initial reactants; at least one connection for introducing the alkylene oxide, such as propylene oxide or ethylene oxide, to the bottom of the autoclave; long with suitable devices for both cooling and heating the autoclave, such as a cooling jacket, and, preferably, coils in addition thereto, with the jacket so arranged that it is suitable for heating with steam or cooling with water and further equipped with electrical heating devices. Such autoclaves are, of course, in essence small-scale replicas of the usual conventional autoclave used in oxyalkylation procedures. In some instances in exploratory preparations an autoclave having a smaller capacity, for instance, approximately 3 liters in one case and about 1% gallons in another case, was used.

Continuous operation, or substantially continuous opera-tion, was chieved by the use of a separate container to hold the alkylene oxide being employed, particularly propylene oxide. In conjunction with the smaller autoclaves, the container consists essentially of a laboratory bomb having a capacity of about one-half gallon, or somewhat in excess thereof. In some instances a larger bomb was used, to Wit, one having a capacity of about one gallon. This bomb was equipped, also, with an inlet for charging, and an eductor tube going to the bottom of the container so as to permit discharging of alkylene oxide in the liquid phase to the autoclave. A bomb having a capacity of about 60 pounds was used in connection with the l-gallon autoclave. Other conventional equipment consists, of course, of the rupture disc, pressure gauge, sight feed glass, thermometer, connection for nitrogen for pressuring bomb, etc. The bomb was placed on a scale during use. The connections between the bomb and the autoclave were flexible stainless steel hose or tubing so that continuous weighings could be made without breaking or making any connections. This applies also to the nitrogen line, which was used to pressure the bomb reservoir. To the extent that it Was required, any other usual conventional procedure or addition which provided greater safety wa used, of course, such as safety glass protective screens, etc.

Attention is directed again to what has been said previously in regard to automatic controls which shut off the propylene oxide in event temperature of reaction passes out of the predetermined range or if pressure in the autoclave asses out of predetermined range.

With this particular arrangement practically all oxypropylation become uniform in that the reaction temperature was held within a few degrees of any selected point, for instance, if 105 C. was selected as the operating temperature the maximum point would be at the most 110 C. or 112 0., and the lower point would be 05 or possibly 98 C. Similarly, the pressure was held at approximately 30 pounds within a S-pound variation one way or the other, but might drop to practically zero, especially where no solvent such as xylene is employed. The speed of reaction was comparatively slow under such conditions as compared with oxyalkylations at 200 C. Numerous reactions were conducted in which the time varied from one day (24 hours) to three days (72 hours), for completion of the final member of a series. In some instances the reaction may take place in considerably less time, i. e., 24 hours or less, as far as a partial oxypropyiation is concerned. The minimum time recorded was about a 3-hour period in a single step. Reactions indicated as being complete in hours may have been complete in a lesser period of time in light of the automatic equipment employed. This applies also where the reactions were complete in a horter period of time, for instance, a to 5 hours. In the ddition of propylene oxide, in the autoclave equipment as far as possible the valves were set so all the propylene oxide if fed continuously would be added at a rate so that the predetermined amount would react within the first hours of the 24-hour period or two-thirds of any shorter period. This meant that if the reaction was interrupted automatically for a period of time for pressure to drop or temperature to drop the predetermined amount of oxide would till be added in most instances well within the predetermined time period. Sometimes where the addition was a comparatively small amount in a 10-hour period there would be an unquestionable speeding up of the reaction, by simply repeating the examples and using 3, 4, or 5 hours instead of 10 hours.

When operating at a comparatively high temperature, for instance, between 150 to 200 0., an unreacted alkylene oxide such as propylene oxide, makes its presence felt in the increase in pressure or the consistency of a higher pressure. However, at a low enough temperature it may happen that the propylene oxide goes in as a liquid. If so, and if it remains unreacted there is, of course, an inherent danger and appropriate steps must be taken to safeguard against this possibility; if need be a sample must be withdrawn and examined for unreacted propylene oxide. One obvious procedure, of course, is to oxypropylate at a modestly higher temperature, for instance, at to C. Unreacted oxide aifects determination of the acetyl or hydroxyl value of the hydroxylated compound obtained.

The higher the molecular weight of the compound, i. e., towards the latter stages of reaction, the longer the time required to add a given amount of oxide. One possible explanation is that the molecule, being larger, the opportunity for random reaction is decreased. Inversely, the lower the molecular weight the faster the reaction takes place. For this reason, sometimes at least, increasing the concentration of the catalyst does not appreciably speed up the reaction, particularly when the product subjected to oxyalkylation has a comparatively high molecular weight. However, as has been pointed out previously, operating at a low pressure and a low temperature even in large scale operations as much as a week or ten days time may lapse to obtain some of the higher molecular weight derivatives from monohydric or dihydric materials.

In number of operations the counterbalance scale or dial scale holding the propylene oxide bomb was so set that when the predetermined amount of propylene oxide had passed into the reaction the scale movement through a time operating device was set for either one or two hours so that reaction continued for 1 to 3 hours after the final addition of the last propylene oxide nd thereafter the operation was shut down. This particular device is particularly suitable for use on larger equipment than laboratory size autoclaves, to wit, on semi-pilot plant or pilot plant size, as Well as on large scale size. This final stirring period is intended to avoid the presence of unreacted oxide.

In this sort of operation, of course, the temperature range was controlled automatically by either use of cooling water, steam, or electrical heat, so as to raise or lower the temperature. The pressuring of the propylene oxide into the reaction vessel was also automatic insofar that the feed stream was set for a slow continuous run which was shut off in case the pressure assed a predetermined point as previously set out. All the points of design, construction, etc., were conventional including the gauges, check valves and entire equipment. As far as I am aware at least two firms, and possibly three, specialize in autoclave equipment such as I have employed in the laboratory, and are prepared to furnish equipment of this same kind. Similarly pilot lant equipment is available. This point is simply made as a precaution in the direction of safety. Oxyalkylations, particularly involving ethylene oxide, glycide, propylene oxide, etc., hould not be conducted except in equipment specifically designed for the purpose.

9 Example 1a The starting material was a commercial grade of benzene sulfonamide. The particular autoclave employed was one with a capacity of gallons or on the average of about 120 pounds of reaction mass. The speed of the stirrer could be varied from 150 to 350 R. P. M. Approximately 7.12 pounds of benzene sulfonamide were charged into the autoclave along with .75 pound of caustic soda. The reaction pot was flushed out with nitrogen. The autoclave was sealed and the automatic devices adjusted and set for injecting a total of 56.25 pounds of propylene oxide in slightly less than a 4-hour period. The pressure regulator was set for a maximum of 35 pounds per square inch. This meant that the bulk of the reaction could take place, and probably did take place, at a lower pressure. This comparatively low pressure was the result of the fact that considerable catalyst was present. The propylene oxide was added comparatively slowly and more important the selected temperature range was 220 to 225 F. (slightly higher than the boiling point of water). The initial introduction of propylene oxide Was not started until the heating devices had raised the temperature to about the boiling point of water. At the completion of the reaction a sample was taken and oxypropylation proceeded as in Example 2a following.

Example 211 temperature as in Example 1a, preceding, except that the reaction period was complete in less time, i. e., 1 hours instead of 3% hours. At the end of the reaction period part of the re- 10 Ewample 4a 49.8 pounds of the reaction mass identified as Example 3a, preceding, were permitted to remain in the autoclave. Without adding any more catalyst this mass was subjected to further oxypropylation as in the preceding examples. The amount of propylene oxide added was slightly less than 27.75 pounds. This was introduced in a, 4-hour period. Conditions in regard to temperature and pressure were substantially the same as in Example 171, preceding. At the end of the reaction period part of the sample was withdrawn and the remainder of the reaction mass was subjected to further oxypropylation as described in Example 5a, following.

Example 5a somewhat short of 10,000, but the increase-inmolecular weight by hydroxyl determination was comparatively small, i. e., just slightly past 3,000.

Incidentally, the above examples were repeated using toluene sulfonamide and for all practical purposes the results obtained were almost identical at each point.

What is said herein is presented in tabular form in Table I immediately following, with some added information as to molecular weight and as to solubility of the reaction product in water, xylene, and kerosene.

TABLE 1 Composition Before Composition at End M. W MaX by Max. Pres. Ex. Time, No. Amide gxide (llatta The? Axmide gxide (llattagggg T213131)" 2 5 1 Hrs.

Amt. int. ys i 0 mt. m ys lbs. lbs. lbs. Wt. lbs. lbs. lbs.

1a 7.12 .75 1,395 7.12 56. .75 1.330 220-225 -37 3 /6 2a... 4. 52 35.73 .47 2,185 4.52 58.35 .47 1,525 220-225 35-37 1% 3a.. 3.16 40.83 .33 3,335 3.16 64.08 .33 2,810 220-225 35-37 2 4a... 2.33 47.15 .27 5,495 2.35 74.03 .27 2,440 220-225 35-37 4 5a... 1.48 47.53 .17 7,015 1.48 64.78 .17 2500 220-225 35-37 5% action mass was withdrawn and employed as a Example 1a was emulsifiable to insoluble in sample and oxypropylation was continued with water, but soluble in xylene and insoluble in the remainder of the reaction mass as described kerosene. Example 2a was insoluble in water,

in Example 307, following.

Emample 3a subjected to oxypropylation as described in Example 4a, following.

soluble in xylene, and insoluble in kerosene. Examples 3a, 4a and 5a were all insoluble in water, soluble in xylene and soluble in kerosene. This was true also of other examples in which the theoretical molecular weight was somewhat higher than the maximum theoretical range indicated above, i. e., a theoretical range of 8,000 to 10,000.

This applied also to samples obtained in substantially the same manner from toluene sulfonchloride. The final product at the end of the oxypropylation step was a somewhat viscous fluid with a slightly reddish tinge. This is characteristic of all the products obtained at the various stages above noted. The products were, of course, slightly alkaline due to the residual caustic soda. The residual basicity due to the catalyst would,

11 of course, be the same if sodium methylate had been used.

Speaking of insolubility in water or solubility in kerosene such solubility test can be made simply by shaking small amounts of the materials in a test tube with water, for instance, using 1% to 5% approximately based on the amount of water present.

Needless to say, there is no complete conversion of propylene oxide into the desired hydroxylated compounds. This is indicated by the fact that the theoretical molecular weight based on a statistical average is greater than the molecular weight calculated by usual methods on basis of acetyl or hydroxyl value. Actually, there is no completely satisfactory method for determining molecular weights of these types of compounds with a high degree of accuracy when the molecular weights exceed 2,000. In some instances the acetyl value or hydroxyl value serves as satisfactorily as an index to the molecular weight as any other procedure, subject to the above limitations, and especially in the higher molecular weight range. If any difficulty is encountered in the manufacture of the esters as described in Part 2 the stoichiometrical amount of acid or acid compound should be taken which corresponds to the indicated acetyl or hydroxyl value. This matter has been discussed in the literature and is a matter of common knowledge and requires no further elaboration.

PART 2 As previously pointed out the present invention is concerned with acidic esters obtained from the propylated derivatives described in Part 1, immediately preceding. and polycarboxy acids, particularly dicarboxy acids such as adipic acid, phthalic acid, or anhydride, succinic acid, diglycollic acid, sebacic acid, azelaic acid, aconitic acid, male'ic acid or anhydride, citraconic acid or anhydride, maleic acid or anhydride adducts as obtained by the Diels-Alder reaction from products such as maleic anhydride, and cyclopentadiene. Such acids should be heat stable so they are not decomposed during esterification. They may contain as many as 36 carbon atoms as, for example, the acids obtained by dimerization of unsaturated fatty acids, unsaturated monocarboxy fatty acids, or unsaturated monocarboxy acids having 18 carbon atoms. Reference to the acid in the hereto appended claims obviously includes the anhydrides or any other obvious equivalents. My preference, however, is to use polycarboxy acids having not over 8 carbon atoms.

The production of esters including acid esters (fractional esters) from polycarboxy acids and glycols or other hydroxylated compounds is well known. Needless to say, various compounds may be used such as the low molal ester, the anhydride, the acyl chloride, etc. However, for purpose of economy it is customary to use either the acid or the anhydride. A conventional procedure is employed. On a laboratory scale one can employ a resin pot of the kind described in U. S. Patent No. 2,499,370, dated March 7, 1950, to De Groote and Keiser, and particularly with one more opening to permit the use of a porous spreader if hydrochloric acid gas is to be used as a catalyst. Such device or absorption spreader consists of minute alundum thimbles which are connected to a glass tube. One can add a sulfonic acid such as paratoluene sulfonic acid as a catalyst. There is some objection to this because in some instances there is some evidence that this acid catalyst tends to decompose or rearrange the oxypropylated compounds, and particularly likely to do so if the esterification temperature is too high. In the case of polycarboxy acids such as diglycollic acid, which is strongly acidic there is no need to add any catalyst. The use of hydrochloric gas has one advantage over para-toluene sulfonic acid and that is that at the end of the reaction it can be removed by flushing out with nitrogen, whereas there is no reasonably convenient means available of removing the paratoluene sulfonic acid or other sulfonic acid employed. If hydrochloric acid is employed one need only pass the gas through at an exceedingly slow rate so as to keep the reaction mass acidic. Only a trace of acid need be present. I have employed hydrochloric acid gas or the aqueous acid itself to eliminate the initial basic material. My preference, however, is to use no catalyst whatsoever and to insure complete dryness of the diol as described in the final procedure just preceding Table 2.

The products obtained in Part 1 preceding may contain a basic catalyst. As a general procedure I have added an amount of half-com centrated hydrochloric acid considerably in excess of what is required to neutralize the residual catalyst. The mixture is shaken thoroughly and allowed to stand overnight. It is then filtered and refiuxed with the xylene present until the water can be separated in a phaseseparating trap. As soon as the product is substantially free from water the distillation stops. This preliminary step can be carried out in the fiask to be used for esterification. If there is any further deposition of sodium chloride during the reflux stage needless to say a second filtration may be required. In any event the neutral or slightly acidic solution of the oxypropylated derivatives described in Part 1 is then diluted further with sufficient xylene, decalin, petroleum solvent, or the like, so that one has obtained approximately a 45% solution. To this solution there is added a polycarboxylated reactant as previously described, such as phthalic anhydride. succinic acid or anhydride, diglycollic acid, etc. The mixture is refluxed until esterification is complete as indicated by elimination of water or drop in carboxyl value. Needless to say, if one produces a half-ester from an anhydride such as phthalic anhydride, no water is eliminated. However, if it is obtained from diglycollic acid, for example, water is eliminated. All such procedures are conventional and have been so thoroughly described in the literature that further consideration will be limited to a few examples and a comprehensive table.

Other procedures for eliminating the basic residual catalyst, if any, can be employed. For

xample, the oxyalkylation can be conducted in absence of a solvent or the solvent removed after oxypropylation. Such oxypropylation end product can then be acidified with just enough concentrated hydrochloric acid to just neutralize the residual basic catalyst. To this product one can then add a small amount of anhydrous sodium sulfate (sufficient in quantity to take up any water that is present) and then subject the mass to centrifugal force so as to eliminate the sodium sulfate and probably the sodium chloride formed. The clear somewhat viscous strawcolored amber liquid so obtained may contain a small amount of sodium sulfate or sodium chlo- 13 ride but, in any event, is perfectly acceptable for esterification in the manner described.

It is to be pointed out that the products here described are not polyesters in the sens that there is a plurality of both diol radicals and acid radicals; the product is characterized by having only one diol radical.

In some instances and, in fact, in many instances I have found that in spite of the dehydration methods employed above that a mere trace of water still comes through and that this mere trace of water certainly interferes with the acetyl or hydroxyl value determination, at least when a number of conventional procedures are used and may retard esterification, particularly where there is no sulfonic acid or hydrochloric acid present as a catalyst. Therefore, I have preferred to use the following procedure: I have employed about 200 grams of the diol as described in Part 1, preceding; I have added about 60 grams of benzene, and then refluxed this mixture in the glass resin pot using a phase-separating trap until the benzene carried out all the water present as Water of solution or the equivalent. Ordinarily this refluxing temperature is apt to be in the neighborhood of 130 to possibly 150 C. When all this water or moisture has 1 been removed I also withdraw approximately Typical distillation data in 9 14 After this material is added, refluxing is continued, and, of course, is at a high temperature, to wit, about 160 to 170 C. If the carboxy reactant is an anhydride needless to say no water of reaction appears; if the carboxy reactant is an acid water of reaction should appear and should be eliminated at the above reaction temperature. If it is not eliminated I simply separate out another 10 to cc. of benzene by means of the phase-separating trap and thus raise the temperature to 180 or 190 C., or even to 200 C., if need be. My preference is not to go above 200 C.

The use of such solvent is extremely satisfactory provided one does not attempt to remove the solvent subsequently except by vacuum distillation and provided there is no objection to a little residue. Actually, when these materials are used for a purpose such as demulsification the solvent might just as well be allowed to remain. If the solvent is to be removed by distillation, and particularly vacuum distillation, then the high boiling aromatic petroleum solvent might well be replaced by some more expensive solvent, such as decalin or an alkylated decalin which has a rather definite or close range boiling point. The removal of the solvent, of course, is purely a conventional procedure and requires no elaboration.

In the appended table solvent #73, which appears in all instances, is a mixture of 7 volumes of the aromatic petroleum solvent previously described and 3 volumes of benzene. This was used, or a similar mixture, in the manner previously described. In a large number of similar examples decalin has been used but it is my preference to use the above mentioned mixture I. P. B., 142 C. m1,, 242 and particularly with the preliminary step of re- 5 m1 m1" C. H moving all the water. If one does not intend to 10 m1" 5 50 m1., 248 C, W remove the solvent my preference is to use the 15 m1., 215 C. ml., 252 C. petroleum solvent-benzene mixture although ob- 20 m1" m1, 5 v1ously any of the other mixtures, such as de- 25 ml., 220 C. ml., 260 C. Calm and Xylene, can be employed. 30 ml., 225 C. ml., 264 C. i The data included in the subsequent tables, 35 1 230 C, ml., 270 C. 1. e., Tables 2 and 3, are self explanator and o a y, 40 m1 1 230 3, very complete and it is bel1eved no further elab- 45 m1" 5 1 307 oration is necessary:

TABLE 2 M0] Theo. Amt. NE 'ci N ci AEcltyl-al Bvgste'd My Ac-id -y bf droxyl dmxyl on Hyd Polycarboxy Reactant g gg Ester Cmpd H. 0. (5 Value Actual ant V. rs)

1c 1, 395 so. 4 84. 5 1, 330 204 Diglycollic Acid 41. 3 1a 1, 395 80.4 54. 5 1, 330 210 Phthalic Anhyd. 45, 7 la 1, 395 80. 4 s4. 5 1, 330 203 Maleic Anhyd. 35, 0 la 1, 395 80. 4 84. 5 1,330 201 Aconitic Acid. 52, 5 la 1,395 80.4 84. 5 1, 330 202 Citraconic Anhy 34 0 2a 2, 185 51. 5 73. 4 1, 525 201 Diglyeollic Acid... 35. 4 2a 2, 185 51. 5 73. 4 1, 525 205 Phthalic Anhyd 40, 5 2c 2, 51. 5 73. 4 1,525 207 Maleic Anhyd 25, 4 2a 2, 51. 5 73. 4 l, 525 208 Aconitic Acid 47 4 2c 2, 185 51. 5 73. 4 1, 525 20s Oitracom'c Aiihyd 35. 5 3a 3, 335 33. 5 4s. 4 2, 310 207 Diglycollic Acid 24. 5 3a 3, 335 33. 5 4s. 4 2, 310 20s Phthalic Ach d 2 7 3a 3, 335 33. 6 48. 4 2, 310 207 Maleic Anhyd. 17. 5 311 3,335 33.5 48.4 2, 310 207 Aconitic Acid. 31.1 3a 3, 335 33. 6 48. 4 2,310 206 Citraconic Anhy 20, 0 3a 3,335 33. 5 4s. 4 2,310 208 Oxalic Acid 22. 4 4a 5, 495 17. 3 45 2,440 205 Diglycollic Acid 22. 4 4a 5, 495 17.3 45 2,440 203 Phthalie Anhyd 25. 2 4c 5, 495 17.3 45 2, 440 20s Maleic Anhyd 15. 8 4c 5, 495 17. 3 45 2,440 207 Aconitic Acid .29. 5 4a 6, 495 17.3 46 2,440 207 Citraeonic Anhyd 19. 0 4a 5, 495 17. 3 45 2, 440 205 Oxalic Acid 2i, 5 5c 7, 015 15.0 43. 2 2, 500 205 Diglycollic Acid 21. 2 5a 7, 015 15. 0 43. 2 2, 500 205 Phthalie Anhyd 23. 5 50 7,015 15.0 43. 2 2, 500 205 Maleic Anhyd. 15. 5 50 7,015 15.0 43. 2 2, 500 205 Aconitlc Acid. 27. 3 5a 7, 015 16.0 43. 2 2,600 208 Citraconic Anhyd l7. 9 55 7,015 15.0 43. 2 2, 500 205 Oxalic Acid 19. 9

TABLE 3 Ex. No. Amt. Esteriflca- Time of Water of Acid Solvent Solvent tion Temp, Esterifica- Out Ester (grs) tion (hrs) (00.)

#7-3 240 149 3% 5. 5 #7 3 257 150 N one #T-S 233 150 1% None #7-3 248 175 4 5. 4 #7 3 236 153 2 None #73 231 156 2 4. 9 #7 3 246 153 5% l\: one #7-3 233 154 3 A one #7-3 250 158 4 4. 9 #73 238 153 None #7-3 228 157 3 3. 2 #7 3 23-1 161 5% 0. 4 $78 225 155 3 1. #7-3 235 174 5. 0 #7-3 226 151 1% None #7-3 220 151 1% 10.3 #7-3 226 161 5 1 #7-3 233 158 6% N one #7-3 225 158 2% N 0110 #7 3 234 163 4% 3. 1 #7-3 226 165 2% N one #7-3 219 146 2 10. 6 #7-3 224 173 3% 3. 0 #7-3 231 152 3% 0. 6 3 222 150 3% None 3 l 229 140 2% 2. 8 #7-3 226 156 2% N ono #7-3 217 165 2% 8. 8

The procedure for manufacturing the esters has been illustrated by preceding examples. If for any reason reaction does not take place in a manner that is acceptable, attention should be directed to the following details: (a) Recheck the hydroxyl or acetyl value of the oxypropylated prodnets of the kind specified and use a stoichiometrically equivalent amount of acid; (b) if the reaction does not proceed with reasonable speed either raise the temperature indicated or else extend the period of time up to 12 or 16 hours if need be; (c) if necessary, use /2% of paratoluene sulfonic acid or some other acid as a catalyst; (d) if the esterification does not produce a clear product a check should be made to see if an inorganic salt such as sodium chloride or sodium sulfate is not precipitating out. Such salt should be eliminated, at least for exploration experimentation, and can be removed by filtering. Everything else being equal as the size of the molecule increases the reactive hydroxyl radical represents a smaller fraction of the entire molecule and thus more difliculty is involved in obtaining complete esterification.

Even under the most carefully controlled controlled conditions of oxypropylation involving comparatively low temperatures and lon time of reaction there are formed certain compounds whose compositions are still obscure. Such side reaction products can contribute a substantial proportion of the final cogeneric reaction mixture. Various suggestions have been made as to the nature of these compounds, such as being cyclic polymers of propylene oxide, dehydration products with the appearance of a vinyl radical, or isomers of propylene oxide or derivatives thereof, i. e., of an aldehyde, ketone, or allyl alcohol. In some instances an attempt to react the stoichiometric amount of a polycarboxy acid with the oxypropylated derivative results in an excess of the carboxylated reactant for the reason that apparently under conditions of reaction less reactive hydroxyl radicals are present than indicated by the hydroxyl value. Under such circumstances there is simply a residue of the carboxylic reactant which can be removed by filtration or, if desired, the esterification procedure can be repeated using an appropriately reduced ratio of carboxylic reactant.

Even the determination of the hydroxyl value and conventional procedure leaves much to be desired due either to the cogeneric materials previously referred to, or for that matter, the presence of any inorganic salts or propylene oxide. Obviously this oxide should be eliminated.

The solvent employed, ii any, can be removed from the finished ester by distillation and particularly vacuum distillation. The final products or liquids are generally pale reddish amber to reddish amber in color, and show moderate viscosity. They can be bleached with bleaching clays, filtering chars, and the like. However, for the purpose of demulsification or the like color is not a factor and decolorization is not justified.

In the above instances I have permitted the solvents to remain present in the final reaction mass. In other instances I have followed the same procedure using decalin or a mixture of decalin or benzene in the same manner and ultimately removed all the solvents by vacuum distillation. Appearances of the final products are much the same as the diols before esterification and in some instances were somewhat darker in color and had a more reddish cast and perhaps somewhat more viscous.

PART 3 Previous reference has been made to the fact that diols (nitrogen-free compounds) such as polypropylene glycol of approximately 2,000 molecular weight, for example, have been esterificd with dicarboxy acids and employed as demulsifying agents. The herein described compounds are different from such diols although both, it is true, are high molecular weight dihydroxylated compounds. The instant compounds have present a nitrogen atom and also a sulfur atom as part of a sulfonamide group. Furthermore, there is pres out a benzene ring. In any event, a combination of nitrogen, sulfur and a benzene ring introduces entirely different characteristics than appear in ordinary polypropylene glycol of a comparable molecular weight. It seems reasonable to assume that the orientation of such molecules are affected by the presence of such particular structure insofar that presumably it would lead to association by hydrogen bonding or some other effect.

Regardless of what the difference may be the fact still remains that the compounds of the kind herein described may be, and frequently are, or better on a quantitative basis than the simpler compound previously described, and demulsify faster and give cleaner oil in many instances. The method of making such comparative tests has been described in a booklet entitled Treating Oil Field Emulsions, used in the Vocational Training Course, Petroleum Inidutstry Series, of the American Petroleum Insti- It may be well to emphasize also the fact that oxypropylation does not produce a single com pound but a cogeneric mixture. The factor involved is the same as appears if one were oxypropylating a monohydric alcohol or a glycol. Momentarily, one may consider the structure of a polypropylene glycol, such as polypropylene glycol of 2000 molecular weight. Propylene glycol has a primary alcohol radical and a secondary alcohol radical. In this sense the building unit which forms polypropylene glycols is not symmetrical. Obviously, then, polypropylene glycols can be obtained, at least theoretically, in which two secondary alcohol groups are united or a secondary alcohol group is united to a priture of closely related or touching homologues.

These materials invariably have high molecular weights and cannot be separated from one another by any known procedure without decomposition. The properties of such mixture represent the contribution of the various individual members of .the mixture. On a statistical basis, of course, n can be appropriately specified. For practical purposes one need only consider the oxypropylation of a monohydric alcohol because in essence this is substantially the mechanism involved. Even in such instances where one is concerned with a monohydric reactant one cannot draw a single formula and say that by following such procedure one can readily obtain 80% or 90%, or 100% of such compound. However, in the case of at least monohydric initial reactants one can readily draw the formulas of a large number of compounds which appear in some of the probable mixtures or can be prepared as components and mixtures which are manufactured conventionally.

Simply by way of illustrating reference is made to the copending application of De Groote, Wirtel and Pettingill, Serial No. 109,791, filed August 11, 1949 (now Patent 2,549,434, granted April 17, 1951).

However, momentarilyv referring again to a monohydric initial reactant it is obvious that if one selects any such simple hydroxylated compound and subjects such compound to oxyalkylation, such as oxyethylation, or oxypropylation, it becomes obvious that one is really producing a polymer of the alkylene oxides except for the terminal group. This is particularly true where the amount of oxide added is comparatively large, for instance, 10, 20, 30, 40, or 50 units. If such compound is subjected to oxyethylation so as to introduce units of ethylene oxide, it is well known that one does not obtain a single constituent which, for the sake of convenience, may be indicated as RO(C2H4O)30H. Instead, one obtains a cogeneric mixture of closely related homologues, in which the formula. may be shown as the following, RO(C2H4O)1LH, wherein n, as far as the statistical average goes, is 30, but the individual members present in significant amount may vary from instances where n has a value of 25, and perhaps less, to a point Where 11. may represent or more. Such mixture is, as stated, a cogeneric closely related series of touching homologous compounds. Considerable investigation has been made in regard to the distribution curves for linear polymers. Attention is directed to the article entitled Fundamental Principles of Condensation Polymerization, by Flory, which appeared in Chemical Reviews, volume 39, No. 1, page 137.

Unfortunately, as has been pointed out by Flory and other investigators, there is no satisfactory method, based on either experimental or mathematical examination, of indicating the e act p oportio o t va ious members of touching homologous series which appear in cogeneric condensation products of the kind described. This means that from the practical standpoint, i. e., the ability to describe how to make the product under consideration and how to repeat such production time after time without difficulty, it is necessary to resort to some other method of description, or else consider the value of n, in formulas such as those which have appeared previously and which appear in the claims, as representing both individual constituents in which n has a single definite value, and also with the understanding that n represents the average statistical value based on the assumption of completeness of reaction.

This may be illustrated as follows: Assume that in any particular example the molal ratio of the propylene oxide to benzene sulfonamide or other specified aromatic sulfonamide, is 30 to 1. Actually, one obtains products in which n probably varies from 10 to 20, perhaps even further. The average value, however, is 15, assuming, as previously stated, that the reaction is complete. The product described by the formula is best described also in terms of method of manufacture.

PART 4 Conventional demulsifying agents employed in the treatment of oil field emulsions are used as such, or after dilution with any suitable solvent, such as water, petroleum hydrocarbons, such as benzene, toluene, Xylene, tar acid oil, cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols, such as methyl alcohol,

material or materials may be used alone or inadmixture with other suitable well-known classes of demulsifying agents.

It is well known that conventional demulsifying agents may be used in a water-soluble form, or in an oil-soluble form, or in a form exhibiting both 011- and water-solubility. Sometimes they may be used in a form which exhibits relatively limited oilsolubility. However, since such reagents are frequently used in a ratio of 1 to 10,000 or 1 to 20,000, or 1 to 30,000, or even 1 to 40,000,

or 1 to 50,000 as in desalting practice, such an apparent insolubility in oil and water is not significant because said reagents undoubtedly have solubility within such concentrations. This same fact is true in regard to the material or materials employed as the demulsifying agent of my process.

In practicing my process for resolving petroleum emulsions of the water-in-oil type, a treating agent or demulsifying agent of the kind above described is brought into contact with or caused to act upon the emulsion to be treated, in any of the various apparatus now generally used to resolve or break petroleum emulsions with achemical reagent, the above procedure being used alone or in combination with other demulsifying, procedure, such as the electrical dehydration process.

Similarly, the material or materials One type of procedure is to accumulate a volume of emulsified oil in. a tank and conduct. a batch treatment .type: of demulsification procedure to recover. clean oil. In thisv procedure the emulsion is admixed with the demulsifier, for example by agitating the tank of emulsion and slowly dripping demulsifier into the emulsion. In some cases mixing is achieved by heating the emulsion While dripping in the demulsifier, depending upon the convection currents in the emulsion to produce satisfactory admixture. In a third modification of this type of treatment, a circulating pump withdraws emulsion from, e. g., the bottom of the tank, and reintroduces it into the top of the tank, the demulsifier being added, for example, at the suction side of said circulating pump.

In a second type of treating procedure, the demulsifier is introduced into the well fluids at the well-head or at some point between the Well-head and the final oil storage tank, by 'means of an adjustable proportioning mechanism or proportioning pump. Ordinarily the flow of fluids through the subsequent lines and fittingssuffices to produce the desired degree of mixing of .demul: sifier and emulsion, although. in some instances additional mixing devices may be introduced into the flow system. In this general procedure, the system may include various mechanical devices for withdrawing free water, separating entrained Water, or accomplishing quiescent settling of the chemicalized emulsion. Heating devices may likewise be incorporated in any of the treating procedures described herein..

A third type of. application (down-the-hole) of demulsifier to emulsion is .to introduce the demulsifier either periodically or continuously in diluted or'undilutedzform int.o;the well and to allow it to come tothe surface;with::the.well fluids, and then to flow. the ;chemicalized.:.emul-. sion through any desirable surface equipment, such as employed in the other :treating ':proce-' dures. This particular type of application .isde

cided y use ul When the:demulsifierJis..'used;in:.

connection with .acidificationzof :calcareoustoilbearing strata, especiallyif suspendedn'nordiss solved in the acid employed for acidification.

In all cases, it Will be apparent. from the row going description, the broad process consists simply in introducing a relatively smallproportion of demulsifier into a relatively large proportion of emulsion, admixing .the chemical. and'lemulsion either through. natural flow or through special apparatus, with .or. without. the application of heat, and allowing ,the mixture to stand qui-.v escent until the undesirable water. content of the emulsion separates and settles from them'ass.

The following is :a atypical. installation;

A reservoirtohold the .demulsifier of the kind described (diluted or.undiluted)i .is placed at the. well-head. where the.- eflluent. liquids I leave the well. Thisreservoir tor container; which" may varyfrom 5 gallons to.50 gallons forconvenience,

is connected to a proportioning pump .which injects the demulsifier drop-wise into the fluids leaving the well.. Such .chemicalized. fluids pass through .;the flowlinejnto: a; settling atank. The

to almost .thezvery; bottomsofastopermit the ins comingfiuids to pass from thetopofi the settling? tank .to the bottom, so that such incoming fluids do not disturb stratification which takes place during, the coursegof,.demulsificationr. The. set

insure thorough distribution of .thedemulsifier' throughout the fluids, or a heater. for raising the temperature .of the fluids to some convenient temperature, for instance, to F., or both heater and mixer..

Emulsification. procedure: isv started. by simply setting the .pumpso -.as .to feed a comparatively large ratio of demulsifier, .forinstance, 1:5,000. As soon as .a complete -.'-break or satisfactory demulsification is. obtained,;.the. pump is regulated .until experienceshowsthat the amount of demulsifier beinggadded.isijust zsufiicient to produce cleaner dehydrated .oil. The amount be ingfed at. such stage is .usually 1: 10,000, 1: 15,000, 1:20,000, or the. like,

In .many instances theoxyalkylated products herein specifiedas. demulsifiers can. be convenientlyused with-out dilution. However, as previ ouslynoted, they'may be v'dilutedas desired with" any suitable solvent. For.instance,;b'y m'ixing'lfi parts by Weight of the .product ofExample-fib' with, 15 parts by weightiof xyleneandlO partsby weight of isopropyl alcohol, an excellent demulsifier is obtained Selection of I thesolvent will vary, depending :upon the solubility ch'arac teristics of f the. oxyalkylated 5 product; and ofcourse .will bedictatedlin part by economic considerations, i. e., cost.

As notedabove, the products herein described may be used1not only. inadiluted form,--but-als'omaybe usedfadmixed with'some other chemical demulsifier."

PART" 5 T Previous reference has beensmade to other.

oxyalkylating. agents other than: propylene oxide, such' as ethylene oxide.

herein but'do produoexmodifications; Benzene sulfonamide or other suitable iaromatic sulfonamide can be reacted with ethylene oxide -inmodest-amounts andthen subjectedto oxypropylation provided that the resultant 1 derivative is (a) .Water-insolubles, .(b) kerosene-soluble, and

(c) has present .15. to .:80:'.alkylene. oxide. radicals. Needless to. say, ini.order..'to. have water-insolubility; and ikeroseneesolubi'lity :the .large majority must be propylene oxide; gest themselves as, for..eXample;-replacing propyl-i ene oxide bybutylene oxide.

More specifically-one mole of benzenesulfom amide;can.be-treated witlr2, 4 or.6 molestof ethylene oxide andfthen trcateclwith. propylene: oxide so as. to producea: water-insoluble, kero-s sene soluble oxyalkylatedsproduct'iniiwhich. theres are present 15 to- 80- oxide radicals as previously specified. Similarly: the rpropylene .oxide canrbe:

added first and then :theeth'ylen'e oxide, or random oxyalkylation can be employed. usingia mix ture .of the .twooxides:

Obviously variants canbe prepared which do not departfromwhat is said Other. variants. sug= The compounds. so ob v tainedrare .readi'ly.iesterifiedinxthe same Fmann'er as described irrBart;2;;preceding;' Incidentally, the :diolsdescribed inrPart .1 .;or the:modifications described therein can be treated with various reactants such as glycide, epichlorohydrim dimethyl sulfate, sulfuric acid, maleic anhydride, ethylene imine, etc. If treated with epichlorohydrin or monochloracetic acid the resultant product can be further reacted with a tertiary amine such as pyridine, or the like, to give quaternary ammonium compounds. If treated with maleic anhydride to give a total ester the resultant can be treated with sodium bisulfite to yield a sulfosuccinate. Sulfo groups can be introduced also by means of a sulfating agent as previously suggested, or by treating the chloroacetic acid resultant with sodium sulfite.

I have found that if such hydroxylated compound or compounds are reacted -further so as to produce entirely new derivatives, such new derivatives have the properties of .the original hydroxylated compound insofar that they are effective and valuable demulsifying agents for resolution of water-in-oil emulsion as found in the petroleum industry, as break inducers in o00H),- in which R, is the radical of a polycarboxy acid and n" is a whole number not over 2; and (B) a compound having 2 reactive hydrogen atoms obtained by the oxypropylation of a sulfonamide and having the formula in which R is a member of the class of aromatic hydrocarbon radicals and oxygen-interrupted aromatic hydrocarbon radicals having a single ether linkage, with the proviso that the entire class be free from any radical having more than '7 uninterrupted carbon atoms in a single group; and R" is selected from the class consisting of hydrogen atoms, and the monovalent radical (CsHsO) n"'H in which n is a whole number not greater than 80; said compound (RI!)N(RI!) being water-insoluble and kerosene-soluble; with the final proviso that the ratio of (A) to (B) be 2 moles of (A) for one mole of (B).

2. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the formula in which R is a member of the class of aromatic hydrocarbon radicals and an oxygen-interrupted aromatic hydrocarbon radical having a single ether linkage, with the proviso that the entire class be free from any radical having more than 7 uninterrupted carbon atoms in a single group; and n and n are Whole numbers with the proviso that n plus n equals a sum varying from 15 to n" is a whole number not over 2 and R is the radical of the polycarboxy acid COOH coom and with the further proviso that the parent dihydroxy compound prior to esterification be water-insoluble and kerosene-soluble.

3. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the formula in which R is a radical containing not more than 7 carbon atoms including the phenyl group; and n and n are whole numbers with the proviso that n plus n equals a sum varying from 15 to 80; n" is a whole number not over 2 and R is the radical of the polycarboxy acid OOOH and with the further proviso that the parent dihydroxy compound prior to esterification be Water-insoluble and kerosene-soluble.

4. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the formula and n and n are whole numbers with the proviso that n plus n equals a sum varying from 15 to 80; n" is a Whole number not over 2 and R is the radical of the polycarboxy acid coon and with the further proviso that the parent dihydroxy compound prior to esterification be water-insoluble and kerosene-soluble.

5. A process for breaking petroleum emulsions of the water-in-oil type characterized 'by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the formula V 6 no 0C) .-R oH6c3),.N c;H60 ,.'0R c0 own having not more than 8 carbon atoms; and with the ;fu11ther.l r0viso that the parent dihydroxy compound ,prior .to esterification bewater-insoluble and-ikerosene-soluble;

6. A process for breaking petroleum emulsionsof the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic-products; said hydrophile synthetic products being characterized by the formula 24 and wand n are -who1'e numbers withthe proviso that nplus-n equals a sumvarying from 15m 80; andR-Zis" the radical of the'dicarboxy acid OOOH having-1110i, more :than Bicarbon atoms; and "with the .funther proviso that :the parent dihydroxy compound: prior r. to esterificationbe: water-insoluble and rkerosenee'soluble '7. The process offclaim GWherein the dicarboxy acid is phthalic acid. l

8: The cprocess ofrclaim fi iwhereinr thedicarboxy acid is-maleiczacidi 9; The process oficlaimfiwherein'the dicarboxy acidis oxalic acids.

10. Therprocesszof claim .6- .wherein the 'dicarboxy acid is citraconic acid.

1 1 The" processilofuclaimfi wherein. the dicarboxy 'acidjsdiglycollic 2acid; v

MELVIN "DEL GROOTE.

REFERENCES CITED The following 1 references are .of record .in, the file of thispatentz.

UNITED STATES PATENTS Number Name Date 2,353,694 De-Groote et al."- July18, 1944 2,562,878 Blair; Aug; 7, 1951 

1. A PROCESS FOR BREAKING PETROLEUM EMULSIONS OF THE WATER-IN-OIL TYPE CHARACTERIZED BY SUBJECTING THE EMULSION TO THE ACTION OF A DEMULSIFIER INCLUDING HYDROPHILE SYNTHETIC PRODUCTS; SAID HYDROPHILE SYNTHETIC PRODUCTS BEING A COGENERIC MIXTURE SELECTED FROM THE CLASS CONSISTING OF ACIDIC FRACTIONAL ESTERS AND ACIDIC AMIDO DERIVATIVES OBTAINED BY REACTION BETWEEN (A) A POLYCARBOXY ACID OF THE STRUCTURE 